Accumulated Other Comprehensive Income (Loss) - Components of Accumulated Other Comprehensive Income (Loss) (Detail) - USD ($) $ in Millions	3 Months Ended		6 Months Ended
	Jun. 30, 2016	Jun. 30, 2015	Jun. 30, 2016	Jun. 30, 2015
Accumulated Other Comprehensive Income (Loss) [Line Items]
Accumulated Other Comprehensive Income (Loss), Beginning balance			$ (127)
Other comprehensive income (loss) before reclassifications, net of tax			62
Amounts reclassified from accumulated other comprehensive (income) loss net of tax			16
Other comprehensive income (loss), net of taxes	$ 9	$ 16	78	$ (57)
Accumulated Other Comprehensive Income (Loss), Ending balance	(49)		(49)
Derivative Instruments [Member]
Accumulated Other Comprehensive Income (Loss) [Line Items]
Accumulated Other Comprehensive Income (Loss), Beginning balance			(52)
Other comprehensive income (loss) before reclassifications, net of tax			(7)
Amounts reclassified from accumulated other comprehensive (income) loss net of tax			16
Other comprehensive income (loss), net of taxes			9
Accumulated Other Comprehensive Income (Loss), Ending balance	(43)		(43)
Available-for-Sale Securities [Member]
Accumulated Other Comprehensive Income (Loss) [Line Items]
Accumulated Other Comprehensive Income (Loss), Beginning balance			8
Other comprehensive income (loss) before reclassifications, net of tax			2
Other comprehensive income (loss), net of taxes			2
Accumulated Other Comprehensive Income (Loss), Ending balance	10		10
Foreign Currency Translation Adjustments [Member]
Accumulated Other Comprehensive Income (Loss) [Line Items]
Accumulated Other Comprehensive Income (Loss), Beginning balance			(75)
Other comprehensive income (loss) before reclassifications, net of tax			67
Other comprehensive income (loss), net of taxes			67
Accumulated Other Comprehensive Income (Loss), Ending balance	(8)		(8)
Post - Retirement Benefit Plans [Member]
Accumulated Other Comprehensive Income (Loss) [Line Items]
Accumulated Other Comprehensive Income (Loss), Beginning balance			(8)
Accumulated Other Comprehensive Income (Loss), Ending balance	$ (8)		$ (8)